The present disclosure relates to infusion therapy with vascular access devices. Infusion therapy is one of the most common health care procedures. Hospitalized, home care, and other patients receive fluids, pharmaceuticals, and blood products via a vascular access device inserted into the vascular system. Infusion therapy may be used to treat an infection, provide anesthesia or analgesia, provide nutritional support, treat cancerous growths, maintain blood pressure and heart rhythm, or many other clinically significant uses.
Infusion therapy is facilitated by a vascular access device. The vascular access device may access a patient's peripheral or central vasculature. The vascular access device may be indwelling for short term (days), moderate term (weeks), or long term (months to years). The vascular access device may be used for continuous infusion therapy or for intermittent therapy.
A common vascular access device is a plastic catheter that is inserted into a patient's vein. The catheter length may vary from a few centimeters for peripheral access to many centimeters for central access. The catheter may be inserted transcutaneously or may be surgically implanted beneath the patient's skin. The catheter, or any other vascular access device attached thereto, may have a single lumen or multiple lumens for infusion of many fluids simultaneously.
Vascular access devices commonly include a Luer adapter, or other connector or adapter, to which other medical devices may be attached. For example, an IV (intravenous) administration set may be attached to a vascular access device to provide a fluid conduit for the continuous infusion of fluids and pharmaceuticals from an intravenous (IV) bag. A variety of medical devices may cooperate with vascular access devices to provide selective, temporary, or long-term access to the vascular system of a patient. A vascular access device may include a body having a lumen through the body and a septum for selectively closing the lumen. The septum may be opened with a blunt cannula, a male Luer of a medical device, or other suitable medical device.
Vascular access devices provide many significant benefits to patients and medical practitioners. A vascular access device is most beneficial to patients when the septum forms a proper seal between the accessed vascular system and the outside or external environment. In an ideal vascular access device, the septum would continuously seal the patient's vascular system, which may include external vascular equipment intentionally coupled to the patient's internal vascular system by a medical practitioner, from the external environment.
As with most systems, one of the biggest challenges to the proper function of the vascular access device is when there is a change in the system, such as when different medical devices are connected or disconnected from the vascular access device. If the seal against the external environment is broken during the connection or disconnection of a medical device, there is the possibility of infection being introduced into the patient's vascular system. Additionally, if a pressure difference is created across the vascular access device, there becomes the possibility that blood will be drawn up the catheter system and possibly into the vascular access device or beyond. Alternatively, a pressure difference across the vascular access device may make it more difficult to couple other medical devices to the vascular access device.
As introduced above, vascular access devices are often coupled with a blunted cannula, such as the tip of a syringe, with a male Luer connector, or with other medical devices. These medical devices may be coupled to the vascular access devices by pressing a portion of the medical device into a slit or passage in the septum. Some medical devices are coupled to the vascular access device through a twisting motion by which the body or other portion of the medical device is coupled to the body of the vascular access device and by which a portion of the medical device is disposed in the slit or passage of the septum. Other methods of coupling the vascular access device to one or more medical devices may be used as well.
Regardless of the methods used to couple medical devices to the vascular access device, repeated transitions of the septum between open and closed configurations applies stress to the septum. In some experiences the septum has been seen to tear, either slightly or more significantly, at the edges of the slit that allows other devices to access the internal vascular system through the lumen of the body. In previous vascular access devices, two common tear patterns have been observed: radial tearing and circumferential tearing. Depending on the nature of the tear, the impacts of the tear may include a decrease in the quality of the seal formed by the septum or pieces or particles of the septum breaking free from the remainder of the septum. In any event, a septum that is modified from the manufacturer's intended and safety-tested design is not preferred for a number of reasons. The present disclosure is directed to vascular access devices, and methods of manufacturing vascular access devices, that include a tear-resistant septum.